Air-brake



No. 608,600. Patented Aug. 9, I898.

F. L. GUlLL-EMET.

AIR BRAKE.-

{Application filed June 3, 1896.)

(No Model.)

WITNESSES:

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UNlllED STATES Fa'rnnrr rrrcn.

FRANQOIS L. GUILLEMET, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR TO THE WESTINGHOUSE AIR BRAKE COMPANY, OF XVILMERD ING,

PENNSYLVANIA.

AIR BRAKE.

SPECIFICATION forming part of Letters Patent No. 608,600, dated August 9, 1898.

Application filed June 3, 1896. Serial No. 594,093. (No model.) A

To all whom it may concern.-

Be it known that 1, Rumors L. GUILLE- MET, a citizen of France, (having declared my intention to become a citizen of the United States,) residing at San Francisco, in the county of San Francisco and State of California, have invented or discovered a certain new and useful Improvement in Air-Brakes, of which improvement the following is a specification.

The object of my invention is to provide an improvement in automatic fluid pressure brake apparatus; and to this end my invention consists in a new and improvedtriplevalve device, in the combination therewith of means for locally releasing fluid under pressure from the train-pipe, and in certain com-j binations and features of, construction, all as hereinafter fully set forth.

In the accompanying drawings, which i1lustrate an application of my invention, Figure 1 is a central longitudinal section of a triplevalve device constructed in accordance with my invention; Fig. 2, a transverse section on the line mm of Fig. 1; Fig.3, a section on the line :1 y of Fig. 1, and Fig. 4 a transverse section of the line are of Fig. 1.-

As shown in Fig. 1 of the drawings, the casing of the triple-valve device consists of two parts or sections 1 and 2, which are se: cured together by, bolts passing through flanges 3, one of which is shown in Fig. 2, and a gasket 4 is fitted between the twosections and between the flanges, so as to make a tight joint. The section 2 of the casing is provided with a flange 5', which is adapted to be secured to a brake-cylinder or auxiliary reservoir, the connections being such that the passages 6 and 7 communicate, respectively, with the auxiliary reservoir and brake-cylinder.

A passage 8, formed in the section 2, is connected with the train-pipe or with a branch therefrom and communicates with a passage 9 in the section 1, which is connected with the triple-valve piston-chamber 10 by a passage 11. Fluid is supplied to the auxiliary reservoir from the chamber 10 through a feedpassage 33 in the bushing 18 and through the passages 34 and 6, and theright-hand side of the piston 17 is at all times exposed to the pressure in the auxiliary reservoir.

f Alocal exhaust-valve12, which is adapted to be unseated in emergency applications of the brakes, controls communication between the passage 9 and the passage 7, leading to the brake-cylinder, and is held to its seat by the pressure of a spring 13, andby fluid, under pressure acting on its upper side or back, which fluid is supplied throughthe passages 9 and 11, chamber 14, and passage to the chamber 16, in which the valve 12 is fitted. The endof the passage7, controlled bythe Valve 12, forms an annular port surrounding the circular end of the passage 9, and the valve 12 is made in the form of a simple disk or thin piston, which .is provided on its face with a gasket, adapted to bear on the edges or annular seats surrounding the ends of the passages 7 and 9.

The triple-valve piston 17 is fitted to slide in a bushing 18 in the chamber 10 and is provided with a hollow extension 19, which projects into the chamber 14 in position to engage with and move the valve 20. The valve 20 is adapted to be engaged by the shoulders 21 and 22 and moved in either direction, and its length is somewhat shorter than the distance between the shoulders 21 and 22, so as to permit a partial movement of the piston 17 independent of the valve 20.

A spring 23, secured to the flanges 24 of the valve 20, tends to hold the valve to its seat, and a cavity 25 in the valve 20 normally connects a passage 26, leading from the brakecylinder passage 7, with an exhaust-passage 27, which opens to the atmosphere.

. WVithin the chamber 28 of the extension 19 is located a spring 29, which bears at one end on a stem 30 and at its other end on a graduating-valve 31, controlling i a passage 32, leading to the brake-cylinder passage 7. The graduating-valve passes through an opening in a screw-cap 35, and the joint is made tight by a gasket or packing 36, which is secured between the screw -cap and a washer or loose collar 37, which bears on the end of the hollow extension 19. The stem 30 fits into the wall of the casing at theend of the chamber 14 and remains stationary when the piston 17 is moved in either direction, the extensionl.) being adapted to slide onthestemSO,

lVhen a comparatively slight reduction of train-pipe pressure is made for the purpose of effecting a service application of the brakes, the piston 17 will be moved to the left, the shoulder 21 on the extension 19 will come in contact with and move the valve 20, so as to close the exhaust-port 27, and after the exhaust-port 27 is closed the collar or washer 37 will come in contact with the flange or shoulder 38 on the graduating-valve 31, and the graduating-valve will be unseated, thereby permitting fluid under pressure to flow from the auxiliary reservoir to the brake-cylinder through the passages 32 and 7. The movement of the piston 17 to the left will be checked by the resistance of the spring 29, which is subject to compression by any movement of the piston to the left beyond the position in which the collar or washer 37 first comes in contact with the flange 38 on the graduating-valve 31. Then the auxiliary-reservoir pressure has nearly equalized with the train-pipe pressure, the piston 17 will be moved to the right by the train-pipe pressure and the pressure of the spring 29 far enough to permit the graduating-valve to close the passage 82 and cut off the flow from the auxiliary reservoir to the brake-cylinder. hen the graduatingvalve is seated, the pressure of the spring 20 no longer acts on the piston 17 to move it to the right, the movement of the piston is checked by the frictional resistance of the valve 20 on its seat, and the valve 20 remains in position to cover the exhaust-passage 27. A further slight reduction of train-pipe pressure will cause the piston to be moved to the left, so as to unseat the graduatingvalve 31, and fluid under pressure will again flow from the auxiliary reservoir to the brake-cylinder until the auxiliary-reservoir and train-pipe pressures have nearly equalized When the graduating-valve will close the passage 32, as before.

WVhen a sufficiently great and rapid reduction of train-pipe pressure is made to effect an emergency application of the brakes, the piston 17 is moved to the limit of its stroke to the left, the flange or annular ridge 39 on the piston 17 bears on the gasket 10, and the rim of the flange 41 on the extension 19 bears on the gasket 42. By this movement of the piston 17 the graduating-valve 31 is unseated and permits fluid under pressure to flow from the auxiliary reservoir to the brakecylinder and the valve 20 is moved to the left, so as to close the exhaust-passage 27 and to put the cavity 25 in the valve 20 into position to connect the passage 15 with the passage 26. Fluid under pressure will then be exhausted from the chamber 16 back of the emergencyvalve 12 through the passages 15, 26, and 7 to the brake-cylinder, the valve 12 will be unseated by the pressure in the passage 9, and fluid under pressure will flow from the train-pipe through the passages 8, 9, and 7 to the brake-cylinder.

chamber 16, which is then in communication with the brake-cylinder.

Fluid under pressure will continue to flow from the auxiliary reservoir through the passages 32 and 7 to the brake-cylinder until the auxiliary -reservoir and brake cylinder pressures have equalized. This equalized pressure will be greater than the reduced pressure in the train-pipe or the pressure in chamber 14;, if the chamber 14 is entirely out off from communication with the auxiliary reservoir and brake-cylinder. In order that the pressure in chamber 14 may equalize with the a'uxiliary-reservoir and brake-cylinder pressure when the piston 17 is at the extremity of its stroke to the left, I provide a passage 43 in the piston 17, through which any fluid under pressure leaking around the packing-ring 14 of the piston 17 may pass into the chamber 28 of the extension 19, and thence around the stem 30 into the chamber 1%. If preferred, the same result may be accomplished by providing a small groove 45 in the bushing 40 of chamber 14, the position of the groove being such that it connects the passage 15 with the chamber 11 when the valve 20 is at the extremity of its stroke to the left. The pressure in the chamber 14, having equalized with the auxiliary-reservoir and brakecylinder pressures, will tend to hold the valve 20 to its seat and, acting on the flange 41, will assist the movement of piston 17 to the right when the train-pipe pressure is increased to release the brakes.

In releasingthe brakes the emergency-valve 12 cannot be unseated by train-pipe pressure,

because the train-pipe pressure acts on a comparatively small area, and the equalized auxiliary-reservoir and brake-cylinder pressure acting on the back of the valve will be suflicient to overcome the pressure in the passages 9 and 7 and will be assisted by the pressure of the spring 13. The train-pipe pressure per unit of area in the passage 9 cannot exceed the pressure per unit of area 011 the back of the valve 12, because the piston 17 will be moved to the right before the trainpipe pressure exceeds the equalized auxiliaryreservoir and brake-cylinder pressures, and this movement of the piston 17 will shift the valve 20, so as to put the chamber 16 in con1- munication with the passage 9 through the passage 15, chamber 1 1, and passage 11.

It will be seen that with my improved c0nstruction the section 1 of the triple-valve casing may be removed without breaking any pipe-joints, the section 2 being permanently fixed to the brake-cylinder orauxiliary reservoir or permanently connected with these parts by means of pipes and the train-pipe being connected with the passage 8 by means of a nozzle formed integral with the section 2.

The emergency-valve is simple in construction and is adapted to operate so as to prevent a return flow of fluid from the brakeoylinder to the train-pipe, and thereby renders the employment of an additional check or non-return valve unnecessary. The position and arrangement of the emergency-valve are such that dirt or oil or grease cannot collect on its face and destroy the gasket or prevent the valve from seating, the horizontal face of the valve offering 110 means for lodgment of particles of dirt or grease.

I claim as my invention and desire to secure by Letters Patent- 1. The combination, in a triple-valve device, of a piston, a valve on the reservoir side of the piston which is operated by the piston and controls the passage of fluid under pressure from the auxiliary reservoir to the brake-cylinder, and an exhaust-valve located on the train-pipe side of the piston and controlling the passage of fluid from the brake-cylinder to the atmosphere, substantially as set forth.

2. The combination, in a triple-valve device, of a piston exposed on one side to trainpipe pressure and on the other side to auxiliary-reservoir pressure, a valve on the reservoir side of the piston controlling a port through which fluid is released from the auxiliary reservoir to the brake-cylinder, and a valve on the train-pipe side of the piston controlling the exhaust of fluid from the brakecylinder to the atmosphere, substantially as set forth.

3. The combination, in a triple-valve device, of a triple-valve piston, a release-valve for exhausting fluid under pressure from the train-pipe and which is exposed to fluid under pressure on its opposite sides, and a valve on the train-pipe side of the piston, which is operated by the piston, and controls the exhaust of fluid from the brake-cylinder to the atmosphere and also the admission to and exhaust of fluid from one side of the releasevalve, substantially as set forth.

4:. The combination, in a triple-valve device, of a piston,'a valve connected to the piston and operated thereby for releasing fluid under pressure from the auxiliary reservoir to the brake-cylinder, a spring tending to hold the valve to its seat and which bears at one end on the valve and at the other end on a stationary part, and means whereby the spring is compressed and the valve unseated by the movement of the piston on a reduction of train-pipe pressure, substantially as set forth.

In testimony whereof I have hereunto set my hand.

FRANooIs L. GUILLEMET.

Witnesses:

LOUIS GELY, DESIRE PERON. 

